BGS Rock Classification Scheme

Ultramafitite - A type of mafite. In the Rock Classification Scheme, it is the fine-grained equivalent of ultramafic-rock. The term may be used as a field classification when an accurate mineral mode from thin section examination, or a chemical analysis, is not available. British Geological Survey Research Report RR/99/06, section 5.2 and fig. 17.

Code UMFT
Description Ultramafitite - A type of mafite. In the Rock Classification Scheme, it is the fine-grained equivalent of ultramafic-rock. The term may be used as a field classification when an accurate mineral mode from thin section examination, or a chemical analysis, is not available. British Geological Survey Research Report RR/99/06, section 5.2 and fig. 17.
Qualifiers No qualifiers currently exist.
Definition Fine grained, av. <0.25mm normal/exotic intrusive/extrusive crystalline rock, CI M>90%, +/- mica/pyroxene/amphibole/olivine/feldspar
Linked data http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/UMFT

CAVEAT

"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.